Existing display devices generally are provided with scan driving circuits for outputting a scan driving signal to drive pixel circuits to work. The scan driving circuit typically has multi-stages driving units, and each stage of the driving units may output a scan driving signal. It may be determined whether the scan driving circuit goes wrong by detecting a discrepancy between a first scan driving signal and a last scan driving signal outputted from the scan driving circuit. In existing detection manners, an output terminal of a last stage of the scan driving circuits is connected to an output terminal, and it is detected whether an output signal is abnormal by using an oscilloscope. However, the existing detection manners are only applicable to display devices for unidirectional scanning, and the existing detection manners can only satisfy detection in one scanning direction even though the display devices are used for bidirectional scanning.